Rosenberg, Adams and Gurevitch (2000). Metawin 2.0. Statistical software
for Meta-Analysis. Sinauer Associates, Inc. provide this formula to
transform t to r.
r=sqrt(t2/(t2+df))
Hope this helps
Miguel Verdu
"Jason Osborne, Ph.D." wrote:
> I am working on a power analysis project- we are reviewing old journal
> articles to calculate observed effect sizes and power. Some of these
> articles, for example reporting t-test results, only give means and
> t-test, no standard deviation. thus, no effect size calculation is
> possible. I was hoping to estimate an effect size by converting a t to
> an r. I seem to remember a formula that relates the two, but am having
> a dickens of a time tracking one down. The one I did track down, for
> calculating t from r, is not that helpful:
>
> t= r * sqrt(n-2)
> -------------
> sqrt(1-r^2)
>
> I want to be able to calculate r from t. I tried algebraically
> manipulating the formula, but never quite got it to where I could do
> this. Any advice?
>
> Alternatively, a formula for converting t or F to eta-squared, which is
> roughly analogous to r-squared, would also be helpful (I know they are
> not exactly analogous).
>
> Thanks in advance,
> Jason
===========================================================================
This list is open to everyone. Occasionally, less thoughtful
people send inappropriate messages. Please DO NOT COMPLAIN TO
THE POSTMASTER about these messages because the postmaster has no
way of controlling them, and excessive complaints will result in
termination of the list.
For information about this list, including information about the
problem of inappropriate messages and information about how to
unsubscribe, please see the web page at
http://jse.stat.ncsu.edu/
===========================================================================
